An armed citizen saved the lives of dozens of parents and children gathered at a back-to-school event in Florida.

Families were taking part in a “Peace in the City” event in a park in Titusville, Florida, when a man who had been involved in a fistfight earlier returned and started shooting.

“A bystander, who was licensed to a carry a firearm, shot the gunman, police said,” WFTV.com reported. “He was taken to a hospital with life-threatening injuries, police said.”

“We are extremely grateful that nobody else was injured in this incident,” Titusville Police Deputy Chief Todd Hutchinson said. “This suspect opened fire at a crowded public park, this could have been so much worse.”

According to WFTV, “After consulting with the State Attorney’s Office, detectives said they do not expect to file charges against the bystander since his actions were within the law, according to the preliminary investigation, police said.”